Influence of diabetes mellitus on immunity to human tuberculosis

Investigation of the knowledge, attitude and practice regarding nutrition in older adults with tuberculosis and diabetes: a cross-sectional study in Eastern China

OBJECTIVES

Older adults with tuberculosis and diabetes have special needs regarding dietary nutrition. This study aimed to investigate the knowledge, attitude and practice (KAP) regarding dietary nutrition among older adults with those two conditions.

DESIGN

Cross-sectional study.

SETTING

Three tertiary medical centres in China.

PARTICIPANTS

Adults over 60 year old diagnosed with tuberculosis and diabetes.

INTERVENTIONS

Between July 2023 and October 2023.

PRIMARY AND SECONDARY OUTCOME MEASURES

Demographic characteristics and KAP scores collected by self-designed questionnaire.

RESULTS

A total of 456 valid questionnaires were analysed, with 261 (57.24%) participants being over 70 years old. The mean scores were 6.84±3.16 (possible range: 0-24) for knowledge, 23.23±2.23 (possible range: 8-40) for attitude and 22.73±3.14 (possible range: 8-40) for practice, respectively. Correlation analysis revealed significant positive correlations between knowledge and attitude (r=0.287, p<0.001), knowledge and practice (r=0.189, p<0.001) and attitude and practice (r=0.176, p<0.001). Structural equation modelling demonstrated that knowledge significantly influenced attitude (β=0.343, 95% CI (0.257 to 0.422), p<0.001) and practice (β=0.245, 95% CI (0.101 to 0.405), p<0.001) and attitude significantly influenced practice (β=0.274, 95% CI (0.146 to 0.405), p<0.001).

CONCLUSIONS

The study highlights a need for improvements in dietary nutrition practices for older adults with tuberculosis and diabetes. Findings emphasise the urgency of enhancing dietary education among this population in China. Implementation of targeted educational programmes is warranted to improve knowledge, foster positive attitudes and encourage healthier dietary practices, ultimately leading to improved patient outcomes and well-being.

Latent tuberculosis infection and diagnostic performance of the tuberculin skin test among type 2 diabetics in Sana'a city, Yemen

BACKGROUND

Tuberculosis (TB) is one of the most widespread infectious diseases worldwide, typically persisting in the body as a latent TB infection (LTBI). Patients with type 2 diabetes have an increased risk of LTBI progressing to active TB. Therefore, this study determined the prevalence and predictors of LTBI and assessed the agreement between tuberculin skin test (TST) and interferon-gamma release assay (IGRA) in diagnosing LTBI among type 2 diabetics in Sana'a city, Yemen.

METHODS

A cross-sectional study was conducted among 150 type 2 diabetics in private health facilities in Sana'a in 2023. Data about demographics, diabetes-related characteristics, and potential risk factors for LTBI were collected using a structured questionnaire. Patients were then screened for LTBI using TST and IGRA. Univariate analysis was used to identify LTBI-associated risk factors, and multivariable binary logistic regression was used to identify independent predictors of LTBI. The agreement between TST and IGRA for diagnosing LTBI was assessed using Cohen's kappa coefficient (κ).

RESULTS

LTBI was prevalent among 29.3% of type 2 diabetics using both types of tests (25.3% with IGRA and 21.3% with TST). Male gender was an independent predictor of LTBI (AOR = 4.4, 95% confidence interval: 1.30-15.08; P = 0.018). However, being employed (AOR = 0.3, 95% CI: 0.09-0.75; P = 0.013) and longer duration since diabetes diagnosis (AOR = 0.3, 95% CI: 0.12-0.98; P = 0.046) were identified as predictors of lower LTBI risk. The agreement between TST and IGRA for the diagnosis of LTBI was 88%, with a good and statistically significant agreement between the two test types (κ = 0.670; P < 0.001).

CONCLUSIONS

LTBI is common among type 2 diabetics seeking medical care in Sana'a city, with about one-third of them possibly being latently infected. A higher LTBI risk can be predicted among males, while a lower risk can be predicted among those employed or being diagnosed with diabetes for at least five years. The TST shows good agreement with IGRA in diagnosing LTBI among type 2 diabetics, supporting its continued use as a cost-effective and easily accessible test for diagnosing LTBI in the country.

The Prevalence of Mycobacterium Tuberculosis Infection in Saudi Arabia: A Systematic Review and Meta-analysis

The prevalence of Tuberculosis (TB) serves as a pivotal metric, reflecting the TB burden within a specific demographic. It quantifies the number of individuals affected by either active TB disease or latent TB (LTBI). Such data is crucial for assessing the efficacy of TB control interventions and determining the demand for diagnostic and treatment services. This study aims to consolidate data on TB infection prevalence in Saudi Arabia from existing literature. Additionally, we stratify this prevalence based on age, professional involvement in healthcare, gender, and region. Our search was conducted in PubMed, Scopus, Cochrane Library, and Web of Science databases to determine relevant studies. The pooled prevalence of TB infection among the total population residing in Saudi Arabia was estimated using a random-effect meta-analysis approach and Comprehensive Meta-Analysis software. The protocol was registered in the PROSPERO International Prospective Register of Systematic Reviews, No: CRD42023400984. We included 21 studies, 11 of which were pooled in the analysis. The overall prevalence was 17%.Regarding the specific population, we found that the prevalence of TB in Saudi Arabia was 9.8% and 26.7% in the general population and the healthcare workers, respectively. Stratifying by age, the highest prevalence was observed in individuals over 50 years (33.0%), while the lowest was in the 10-19 age group (6.4%). In terms of gender, men had a higher prevalence (12.0%) compared to women (9.4%). The prevalence of TB in Riyadh was 6.4%, and 3.6% in Mecca and Medina. Among healthcare workers, nurses and physicians had a prevalence of 14.7% and 15.0%, respectively. Our study found a TB prevalence of 17.0% in Saudi Arabia, higher than the worldwide average of 12.0%. Men had a higher prevalence than women, and healthcare workers had a relatively low prevalence compared to other countries. Age was a significant risk factor, with the highest prevalence in individuals above 50 years. Standardized protocols for screening and diagnosis and targeted interventions are needed to combat TB effectively in the country.

A blood-based 3-gene signature score for therapeutic monitoring in patients with pulmonary tuberculosis

OBJECTIVE

To assess the validity of Xpert Tuberculosis Fingerstick score for monitoring treatment response and analyze factors influencing its performance.

METHODS

122 adults with pulmonary tuberculosis were recruited and stratified into three cohorts: Diabetic-drug-susceptible-TB (DM-TB), Non-diabetic-drug-susceptible-TB (NDM-TB) and Non-diabetic Multidrug-resistant TB (MDR-TB). Fingerstick blood specimens were tested at treatment initiation (M0) and the end of the first (M1), second (M2), and sixth month (M6) to generate a TB-score.

RESULTS

The TB-score in all participants yielded an AUC of 0.707 (95% CI: 0.579-0.834) at M2 when its performance was evaluated against sputum culture conversion. In all non-diabetes patients, the AUC reached 0.88 (95% CI: 0.756-1.000) with an optimal cut-off value of 1.95 at which sensitivity was 90.0% (95% CI: 59.6-98.2%) and specificity was 81.3% (95% CI: 70.0-88.9%). The mean TB score was higher in patients with low bacterial loads (n = 31) than those with high bacterial loads (n = 91) at M0, M1, M2, and M6, and was higher in non-cavitary patients (n = 71) than those with cavitary lesions (n = 51) at M0, M1, and M2.

CONCLUSION

Xpert TB-score shows promising predictive value for culture conversion in non-diabetic TB patients. Sputum bacterial load and lung cavitation status have an influence on the value of TB score.

Impact of hyperglycemia on tuberculosis treatment outcomes: a cohort study

Hyperglycemia is prevalent and closely associated with pulmonary tuberculosis (PTB). This study aimed to investigate the effects of hyperglycemia on the outcomes of PTB treatment. This study comprised 791 patients with PTB in total. Patients with fasting plasma glucose levels of ≥ 6.1 mmol/L were diagnosed with hyperglycemia. Anthropometric and baseline demographic data were also collected. The treatment response was assessed based on clinical symptoms (sputum production, cough, chest pain, fever, hemoptysis, night sweats, loss of appetite, and fatigue), sputum smear, chest computed tomography (CT), and adverse gastrointestinal responses (vomiting, nausea, abdominal distension, diarrhea, and constipation). A generalized estimating equation (GEE) was used to evaluate these relationships. Hyperglycemia affected 266 (33.6%) of the 791 patients with PTB. In GEE analyses, patients with hyperglycemia exhibited a greater incidence of elevated tuberculosis (TB) scores (odds ratio (OR) 1.569; 95% CI 1.040-2.369), cough (OR 1.332; 95% CI 1.050-1.690), and night sweats (OR 1.694; 95% CI 1.288-2.335). Hyperglycemia was linked with a higher risk of positive sputum smears (OR 1.941; 95% CI 1.382-2.727). During therapy, hyperglycemia was also associated with an increased incidence of vomiting (OR 2.738; 95% CI 1.041-7.198), abdominal distension (OR 2.230; 95% CI 1.193-4.171), and constipation (OR 2.372; 95% CI 1.442-3.902). However, the CT results indicated that hyperglycemia did not affect pulmonary lesions in patients with TB. Patients with TB and hyperglycemia are at a higher risk of severe clinical manifestations, positive sputum smears, and adverse gastrointestinal effects and, therefore, the special situation of hyperglycemic patients should be considered in the prevention and treatment of TB.

Clinical features, immunologic parameter and treatment outcome of Chinese tuberculosis patients with or without DM

Background

The coexistence of diabetes mellitus (DM) and pulmonary tuberculosis (PTB) poses a significant health concern globally, with their convergence presenting a considerable challenge to healthcare systems. Previous research has highlighted that comorbidities can mutually influence and exacerbate immune disorders. However, there is a paucity of data on the impact of DM on immunological features and treatment responses in the TB population in China.

Methods

From January 2020 to June 2022, 264 cases of pulmonary tuberculosis patients (82 DM patients and 182 non-DM patients) hospitalized in our center were selected. 80 patients with TB with DM (TB-DM) and 80 patients with TB without DM (TB-NDM) were enrolled into the final analysis by propensity score matching for age, gender and involved lung field at a ratio of 1:1. The clinical characteristics, immunological features and treatment response were compared between the two groups.

Results

After propensity score matching, no differences in the general features such as age gender, involved lung field, the incidence of retreatment and WBC count were found between the two groups. Compared to TB-NDM group, the TB-DM group exhibited a higher positive rate of sputum smear and incidence of cavitary lesions. Immunological features analysis revealed that the TB-DM patients had higher levels of TNF-α [pg/ml; 8.56 (7.08-13.35) vs. 7.64 (6.38-10.14) p = 0.033] and IL-8 [pg/ml; 25.85 (11.63-58.40) vs. 17.56 (6.44-39.08) p = 0.003] but lower CD8+ T lymphocyte count [cells/mm3; 334.02 (249.35-420.71) VS 380.95 (291.73-471.25) p = 0.038]. However, there was no significant difference in serum IL-6 concentration and CD4+ T lymphocyte count between the two groups. After 2 months of anti-tuberculosis treatment, 39 (24.4%) cases had suboptimal treatment response, including 23 (28.7%) TB-DM patients and 16 (20%) TB-NDM patients. There was no difference in suboptimal response rate (SRR) was found between the two groups (p = 0.269). The multivariate logistic regression analysis indicated that retreatment for TB [AOR: 5.68 (95%CI: 2.01-16.08), p = 0.001], sputum smear positivity [AOR: 8.01 (95%CI: 2.62-24.50), p = 0.001] were associated with SRR in all participants, and in TB-DM group, only sputum smear positivity [AOR: 16.47 (1.75-155.12), p = 0.014] was positive with SRR.

Conclusion

DM is a risk factor for pulmonary cavity formation and sputum smear positivity in TB population. Additionally, TB-DM patients is characterized by enhanced cytokine responses and decreased CD8+ T lymphocytes. The retreatment for TB and sputum smear positivity were associated with the occurrence of suboptimal treatment response.

Determinants of tuberculosis disease development in children in central Ethiopia: A matched case-control study

BACKGROUND

The risk factors for tuberculosis (TB) disease development in children remained understudied, particularly in low-income countries like Ethiopia. The objective of this study was to identify determinants of TB disease development in general and in relation to BCG vaccination in children in central Ethiopia.

METHODS

We employed a 1:1 age-matched case-control design to compare the characteristics of children who developed TB (cases) with those who did not (controls). Data were collected in healthcare facilities in Addis Ababa city, Adama, and Bishoftu towns between September 25, 2021, and June 24, 2022. Two hundred and fifty-six cases were drawn at random from a list of childhood TB patients entered into SPSS software, and 256 controls were selected sequentially at triage from the same healthcare facilities where the cases were treated. A bivariate conditional logistic regression analysis was performed first to select candidate variables with p-values less than or equal to 0.20 for the multivariable model. Finally, variables with a p-value less than 0.05 for a matched adjusted odds ratio (mORadj) were reported as independent determinants of TB disease development.

RESULTS

The mean age of the cases was nine years, while that of the controls was 10 years. Males comprised 126 cases (49.2%) and 119 controls (46.5%), with the remainder being females. Ninety-nine (38.7%) of the cases were not BCG-vaccinated, compared to 58 (22.7%) of the controls. Household TB contact was experienced by 43 (16.8%) of the cases and 10 (3.9%) of the controls. Twenty-two (8.6%) of the cases and six (2.3%) of the controls were exposed to a cigarette smoker in their household. Twenty-two (8.6%) of the cases and three (1.2%) of the controls were positive for HIV. Children who were not vaccinated with BCG at birth or within two weeks of birth had more than twice the odds (mORadj = 2.11, 95% CI = 1.28-3.48) of developing TB compared to those who were. Children who ever lived with a TB-sick family member (mORadj = 4.28, 95% CI = 1.95-9.39), smoking family members (mORadj = 3.15, 95% CI = 1.07-9.27), and HIV-infected children (mORadj = 8.71, 95% CI = 1.96-38.66) also had higher odds of developing TB disease than their counterparts.

CONCLUSIONS

Being BCG-unvaccinated, having household TB contact, having a smoker in the household, and being HIV-infected were found to be independent determinants of TB disease development among children.

Prevalence of Drug-Resistant Tuberculosis in HIV-Positive and Diabetic Patients in Sinaloa, Mexico: A Retrospective Cross-Sectional Study

Tuberculosis (TB) is a disease caused by the bacillus Mycobacterium tuberculosis (MTB). Human immunodeficiency virus (HIV) infection and type 2 diabetes mellitus (T2DM) are among the main risk factors for the development of TB and increase the risk of drug-resistant TB developing (DR-TB). The aim of this study was to estimate the prevalence of DR-TB in patients with HIV or T2DM in Sinaloa, Mexico. This was an observational and cross-sectional study. The analysis was conducted using the clinical data of patients registered on the National Epidemiological Surveillance System for TB (SINAVE/PUI-TB) platform with a presumed diagnosis of TB during 2019 to 2021 in Sinaloa, Mexico. The prevalence of DR-TB was estimated in HIV and T2DM patients, as well as the odds ratios for their sociodemographic variables, using the Chi-square test. There were 2, 4, and 4 TB-HIV cases and 2, 6, and 9 TB-T2DM cases during 2019, 2020, and 2021, respectively, whereas there were 2 and 1 DRTB-HIV and DRTB-T2DM cases, respectively. The results indicated that the WHO guidelines for DR-TB were not properly applied to this high-risk population. Hence, the appropriate application of guidelines for TB and DR-TB detection in these patients needs to be immediately implemented by the State health system.

A Comparative Investigation on Cytokine Expression in Pulmonary Tuberculosis and Comorbidity with Type 2 Diabetes Mellitus

BACKGROUND

Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), with a high global prevalence and mortality rate. To control the gruesome pathogen, a deep understanding of pathophysiology and host-pathogen interaction is essential for early diagnosis and novel drug development. Cytokines play a crucial role in infection and susceptibility, and their expressions could serve as potential biomarkers to enhance our understanding of Mtb pathophysiology for improved therapeutic approaches. This cross-sectional study investigates the levels of four important T-cell immune-mediated cytokines: interleukins (IL-6 and IL-10), interferon-gamma (IFN-γ), and tumor necrosis factor-alpha in 80 cohort samples, with 20 people in each group.

METHODS

Following proper ethics and patient consent, we collected blood samples and isolated serum from all four groups: TB, type 2 diabetes mellitus (T2DM), type 2 diabetes-TB comorbidity (T2DM + TB), and a healthy individual as a control group (C). Furthermore, cytokine expression was measured in individual serum samples through the enzyme-linked immunosorbent assay method using commercial kits (Diaclone, French). Statistical significance was observed by analyzing triplicate data using t-tests and the one-way ANOVA method with GraphPad Prism 10.

RESULTS

The results showed that all four cytokine levels were higher (P ≤ 0.0001) than the control, especially IL-6, IL-10, and IFN-γ, which were found to be upregulated in T2DM + TB samples (P ≤ 0.0001) than individual TB or T2DM samples.

CONCLUSION

The high levels of cytokines in comorbidity cases raise the risk of insulin resistance and the severity of TB infection. These levels of expression could be used to keep track of the Mtb infection status or severity, aid in early diagnosis as a possible biomarker, and suggest possible treatment plans.

Revisiting the association between vitamin D deficiency and active tuberculosis: A prospective case-control study in Taiwan

BACKGROUND

To revisit the association between vitamin D deficiency (VDD, defined as serum 25(OH)D < 20 ng/ml) and incident active tuberculosis (TB), after two potentially underpowered randomized trials showed statistically non-significant 13%-22% decrease in TB incidence in vitamin D supplementation groups.

METHODS

We prospectively conducted an age/sex-matched case-control study that accounting for body-mass index (BMI), smoking, and other confounding factors to examine the association between VDD and active TB among non-HIV people in Taiwan (latitude 24°N), a high-income society which continues to have moderate TB burden.

RESULTS

We enrolled 62 people with incident active TB and 248 people in control group. The TB case patients had a significantly higher proportion of VDD compared to the control group (51.6% vs 29.8%, p = 0.001). The 25(OH)D level was also significantly lower in TB patients compared to control group (21.25 ± 8.93 ng/ml vs 24.45 ± 8.36 ng/ml, p = 0.008). In multivariable analysis, VDD (adjusted odds ratio [aOR]: 3.03, p = 0.002), lower BMI (aOR: 0.81, p < 0.001), liver cirrhosis (aOR: 8.99, p = 0.042), and smoking (aOR: 4.52, p = 0.001) were independent risk factors for incident active TB.

CONCLUSIONS

VDD is an independent risk factor for incident active TB. Future randomized trials examining the effect of vitamin D supplementation on TB incidence should focus on people with a low BMI or other risk factors to maximize the statistical power.

Metformin has immunomodulatory effects which support its potential use as adjunctive therapy in tuberculosis

Metformin is the preferred oral medication for patients with type 2 diabetes mellitus, and this blood glucose-lowering and insulin-sensitizing drug has immunomodulatory effects that could contribute to the management of patients with various other autoimmune and infectious diseases. Tuberculosis is one such infection, and it remains prevalent worldwide, largely due to the successful evasion of the host's immune responses by the infecting pathogen, Mycobacterium tuberculosis. This review focuses on the possible mechanisms relevant to metformin's modulation of innate and adaptive immune responses to Mycobacterium tuberculosis and its potential use as an adjunctive drug in the treatment of tuberculosis. Current data suggest that metformin increases autophagy, phagocytosis, and mitochondrial reactive oxygen species production, while limiting excess inflammation and tissue destruction. This multifaceted drug also augments cell-mediated immune responses by maintaining CD8+ T cell metabolic homeostasis and improving immunological memory. Several murine models have demonstrated that metformin can reduce tuberculosis severity and tissue pathology, and two in vitro human studies confirmed enhanced immune responses in metformin-treated cells. These studies provide convincing evidence supporting the use of metformin to augment immune responses in patients with tuberculosis.

Treatable traits and challenges in the clinical management of non-tuberculous mycobacteria lung disease in people with cystic fibrosis

INTRODUCTION

Over the last ten years an increasing prevalence and incidence of non-tuberculous mycobacteria (NTM) has been reported among patients with cystic fibrosis (CF) Viviani (J Cyst Fibros, 15(5):619-623, 2016). NTM pulmonary disease has been associated with negative clinical outcomes and often requires pharmacological treatment. Although specific guidelines help clinicians in the process of diagnosis and clinical management, the focus on the multidimensional assessment of concomitant problems is still scarce.

MAIN BODY

This review aims to identify the treatable traits of NTM pulmonary disease in people with CF and discuss the importance of a multidisciplinary approach in order to detect and manage all the clinical and behavioral aspects of the disease. The multidisciplinary complexity of NTM pulmonary disease in CF requires careful management of respiratory and extra-respiratory, including control of comorbidities, drug interactions and behavioral factors as adherence to therapies.

CONCLUSIONS

The treatable trait strategy can help to optimize clinical management through systematic assessment of all the aspects of the disease, providing a holistic treatment for such a multi-systemic and complex condition.

The association between type 2 diabetes and pulmonary cavitation revealed among IGRA-positive tuberculosis patients

The co-occurrence of tuberculosis (TB) and diabetes mellitus (DM) presents a significant obstacle to TB eradication. Pulmonary cavitation can occur in severe cases of TB, particularly in patients with DM. From 1 May 2014 through 30 June 2019, we conducted a cross-sectional study of 1,658 smear- or culture-confirmed pulmonary TB (PTB) patients at the Second Department of Pulmonary Medicine and Tuberculosis, Shenzhen, China. A total of 861 participants who satisfied the criteria (chest CT scan for cavitation, interferon-gamma release assay (IGRA), diagnosis of diabetes mellitus), with the median age of 36.7 years, 63.6% of male, 79.7% IGRA positive, 13.8% with diabetes, and 40.8% with pulmonary cavitation, were included in the study. The association between diabetes and pulmonary cavitation was confirmed in these TB patients (adjusted OR, 2.54; 95% CI, 1.66-3.94; p < 0.001). No associations were observed between diabetes and IGRA, as well as between lung cavitary and IGRA. Based on the criteria of IGRA+/-, pulmonary cavitation+/-, and DM+/-, the further analysis with univariate and multivariate logistic regression were conducted in six subgroups. The significant association between diabetes and pulmonary cavitation was further confirmed in the IGRA+ subgroup (adjusted OR, 3.07; 95% CI, 1.86-5.16; p < 0.001) but not observed in IGRA- individuals. This observation suggests that different immunological mechanisms of pulmonary cavitary/DM may be employed in IGRA+ TB patients from IGRA- TB patients.

Quantitative proteomics reveals plasma protein profile and potential pathways in pulmonary tuberculosis patients with and without diabetes

BACKGROUND

The coexistence of pulmonary tuberculosis (PTB) and diabetes mellitus (DM) has emerged as a significant global public health concern. Patients with DM are at higher risk of developing PTB, and PTB is one of the important factors that exacerbate the development of DM. However, the impact of DM on the protein profile and underlying pathways in PTB patients is unclear.

METHODS

We systematically used data-independent acquisition (DIA)-based liquid chromatography - tandem mass spectrometry (LC-MS/MS) to identify differentially expressed proteins (DEPs) in plasma samples from PTB patients, DM combined with PTB patients, and healthy controls. Then these DEPs were analyzed by bioinformatics.

RESULTS

Our analysis identified 268 proteins, the results indicated that DEPs in the PTB group as well as in the DM-PTB group were mainly involved in immune responses, complement and coagulation cascade and cholesterol metabolic pathways compared to healthy controls.

CONCLUSIONS

We analyzed the plasma protein profiles of PTB, DM-PTB, and HC groups using proteomics techniques and identified potential pathways for PTB patients with and without DM. This provides valuable clues to explore the impact of DM on PTB.

The effect of diabetes mellitus on tuberculosis in eastern China: A decision-tree analysis based on a real-world study

OBJECTIVES

The public health system faces major challenges due to the double burden of diabetes mellitus (DM) and tuberculosis (TB) in China. We aimed to investigate the prevalence and impact of diabetes on patients with TB.

METHODS

Stratified cluster sampling was used to select 13 counties as study sites in the Zhejiang province. Patients who visited designated TB hospitals in these areas participated in this study between 1 January 2017 and 28 February 2019. Multiple logistic regression models were performed to investigate the association between DM and bacteriological and imaging results. A decision tree was used to predict the bacteriology and imaging results under the influence of DM.

RESULTS

Of 5920 patients with newly diagnosed pulmonary tuberculosis, 643 (12.16%) had DM. Patients with pulmonary TB and DM were more likely to have pulmonary cavities (adjusted odds ratio [aOR], 2.81; 95% confidence intervals [95% CI]: 2.35-3.37) and higher rates of positive bacteriological tests (aOR, 2.32; 95% CI:1.87-2.87). Decision-tree analysis showed similar results.

CONCLUSIONS

Concurrence of DM and pulmonary TB makes patients more likely to have positive bacteriological results and pulmonary cavities. Therefore, appropriate measures are necessary to promptly identify and manage patients with TB and DM.

Tuberculosis and COVID-19 in the elderly: factors driving a higher burden of disease

Mycobacterium tuberculosis (M.tb) and SARS-CoV-2 are both infections that can lead to severe disease in the lower lung. However, these two infections are caused by very different pathogens (Mycobacterium vs. virus), they have different mechanisms of pathogenesis and immune response, and differ in how long the infection lasts. Despite the differences, SARS-CoV-2 and M.tb share a common feature, which is also frequently observed in other respiratory infections: the burden of disease in the elderly is greater. Here, we discuss possible reasons for the higher burden in older adults, including the effect of co-morbidities, deterioration of the lung environment, auto-immunity, and a reduced antibody response. While the answer is likely to be multifactorial, understanding the main drivers across different infections may allow us to design broader interventions that increase the health-span of older people.

The cause-effect relation of tuberculosis on incidence of diabetes mellitus

Tuberculosis (TB) is one of the oldest human diseases and is one of the major causes of mortality and morbidity across the Globe. Mycobacterium tuberculosis (Mtb), the causal agent of TB is one of the most successful pathogens known to mankind. Malnutrition, smoking, co-infection with other pathogens like human immunodeficiency virus (HIV), or conditions like diabetes further aggravate the tuberculosis pathogenesis. The association between type 2 diabetes mellitus (DM) and tuberculosis is well known and the immune-metabolic changes during diabetes are known to cause increased susceptibility to tuberculosis. Many epidemiological studies suggest the occurrence of hyperglycemia during active TB leading to impaired glucose tolerance and insulin resistance. However, the mechanisms underlying these effects is not well understood. In this review, we have described possible causal factors like inflammation, host metabolic changes triggered by tuberculosis that could contribute to the development of insulin resistance and type 2 diabetes. We have also discussed therapeutic management of type 2 diabetes during TB, which may help in designing future strategies to cope with TB-DM cases.

PP19128R, a Multiepitope Vaccine Designed to Prevent Latent Tuberculosis Infection, Induced Immune Responses In Silico and In Vitro Assays

Background: Latent tuberculosis infection (LTBI) is the primary source of active tuberculosis (ATB), but a preventive vaccine against LTBI is lacking. Methods: In this study, dominant helper T lymphocyte (HTL), cytotoxic T lymphocyte (CTL), and B-cell epitopes were identified from nine antigens related to LTBI and regions of difference (RDs). These epitopes were used to construct a novel multiepitope vaccine (MEV) based on their antigenicity, immunogenicity, sensitization, and toxicity. The immunological characteristics of the MEV were analyzed with immunoinformatics technology and verified by enzyme-linked immunospot assay and Th1/Th2/Th17 cytokine assay in vitro. Results: A novel MEV, designated PP19128R, containing 19 HTL epitopes, 12 CTL epitopes, 8 B-cell epitopes, toll-like receptor (TLR) agonists, and helper peptides, was successfully constructed. Bioinformatics analysis showed that the antigenicity, immunogenicity, and solubility of PP19128R were 0.8067, 9.29811, and 0.900675, respectively. The global population coverage of PP19128R in HLA class I and II alleles reached 82.24% and 93.71%, respectively. The binding energies of the PP19128R-TLR2 and PP19128R-TLR4 complexes were -1324.77 kcal/mol and -1278 kcal/mol, respectively. In vitro experiments showed that the PP19128R vaccine significantly increased the number of interferon gamma-positive (IFN-γ⁺) T lymphocytes and the levels of cytokines, such as IFN-γ, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-10. Furthermore, positive correlations were observed between PP19128R-specific cytokines in ATB patients and individuals with LTBI. Conclusions: The PP19128R vaccine is a promising MEV with excellent antigenicity and immunogenicity and no toxicity or sensitization that can induce robust immune responses in silico and in vitro. This study provides a vaccine candidate for the prevention of LTBI in the future.

Effect of Immunomodulating Extract and Some Isolates from Etlingera rubroloba A.D. Poulsen Fruits on Diabetic Patients with Tuberculosis

Diabetes mellitus (DM) is a disease easily complicated by tuberculosis (TB) due to impaired function of the innate immune response. The successes of the discovery of immunomodulatory compounds needs to be continued to introduce new insights into the innate immune response. In previous studies, plant compounds of Etlingera rubroloba A.D. Poulsen (E.rubroloba) were demonstrated to have potential as an immunomodulators. This study aims to isolate and identify the structure of the compounds of E.rubroloba fruit that could effectively improve the function of the innate immune response in individuals with DM infected with TB. The isolation and purification of the compounds of the E.rubroloba extract were carried out by radial chromatography (RC) and thin-layer chromatography (TLC). Identification of the isolated compound structures was determined by measuring the proton (¹H) and carbon (¹³C) nuclear magnetic resonance (NMR). In vitro testing was performed on the immunomodulating activity of the extracts and isolated compounds on DM model macrophages infected with TB antigens. This study succeeded at isolating and identifying the structures of two isolate compounds, namely Sinaphyl alcohol diacetat (BER-1), and Ergosterol peroxide (BER-6). The two isolates were more effective as immunomodulators than the positive controls were, which differed significantly (* p < 0.05) at the reducing interleukin-12 (IL-12) levels and Toll-like receptor-2 (TLR-2) protein expression and increasing the human leucocyte antigen-DR (HLA-DR) protein expression in DM infected with TB. The isolated compound was discovered in E. rubroloba fruits, which has been reported to have the potential to be developed as an immunomodulatory agent. Follow-up testing to determine the mechanism and effectiveness of these compounds as immunomodulators for DM patients is required so that they are not susceptible to TB infection.

Cell death induced by NLRP3-palmitate axis impairs pulmonary damage tolerance and aggravates immunopathology during obesity-tuberculosis comorbidity

A low-grade and persistent inflammation, which is the hallmark of obesity, requires the participation of NLRP3 and cell death. During Mycobacterium tuberculosis infection, NLRP3 signaling is important for bacterial killing by macrophages in vitro but was shown to be dispensable for host protection in vivo. We hypothesized that during obesity-tuberculosis (TB) comorbidity, NLRP3 signaling might play a detrimental role by inducing excessive inflammation. We employed a model of high-fat-diet-induced obesity, followed by M. tuberculosis infection in C57BL/6 mice. Obese mice presented increased susceptibility to infection and pulmonary immunopathology compared to lean mice. Using treatment with NLRP3 antagonist and Nlrp3^-/- mice, we showed that NLRP3 signaling promoted cell death, with no effect in bacterial loads. The levels of palmitate were higher in the lungs of obese infected mice compared to lean counterparts, and we observed that this lipid increased M. tuberculosis-induced macrophage death in vitro, which was dependent on NLRP3 and caspase-1. At the chronic phase, although lungs of obese Nlrp3^-/- mice showed an indication of granuloma formation compared to obese wild-type mice, there was no difference in the bacterial load. Our findings indicate that NLRP3 may be a potential target for host-directed therapy to reduce initial and severe inflammation-mediated disease and to treat comorbidity-associated TB. © 2022 The Pathological Society of Great Britain and Ireland.

Advancing personalized medicine for tuberculosis through the application of immune profiling

While early and precise diagnosis is the key to eliminating tuberculosis (TB), conventional methods using culture conversion or sputum smear microscopy have failed to meet demand. This is especially true in high-epidemic developing countries and during pandemic-associated social restrictions. Suboptimal biomarkers have restricted the improvement of TB management and eradication strategies. Therefore, the research and development of new affordable and accessible methods are required. Following the emergence of many high-throughput quantification TB studies, immunomics has the advantages of directly targeting responsive immune molecules and significantly simplifying workloads. In particular, immune profiling has been demonstrated to be a versatile tool that potentially unlocks many options for application in TB management. Herein, we review the current approaches for TB control with regard to the potentials and limitations of immunomics. Multiple directions are also proposed to hopefully unleash immunomics' potential in TB research, not least in revealing representative immune biomarkers to correctly diagnose TB. The immune profiles of patients can be valuable covariates for model-informed precision dosing-based treatment monitoring, prediction of outcome, and the optimal dose prediction of anti-TB drugs.

Immunological aspects of host-pathogen crosstalk in the co-pathogenesis of diabetes and latent tuberculosis

Introduction

Diabetes is a potent risk factor for the activation of latent tuberculosis and worsens the tuberculosis (TB) treatment outcome. The major reason for mortality and morbidity in diabetic patients is due to their increased susceptibility to TB. Thus, the study was conducted to understand the crosstalk between M. tuberculosis and its host upon latent tuberculosis infection and under hyperglycemic conditions or diabetes.

Methods

An animal model was employed to study the relationship between latent tuberculosis and diabetes. BCG immunization was done in mice before infection with M. tuberculosis, and latency was confirmed by bacillary load, histopathological changes in the lungs and gene expression of hspX, tgs1, tgs3 and tgs5. Diabetes was then induced by a single high dose of streptozotocin (150 mg/kg body weight). Host factors, like various cytokines and MMPs (Matrix metalloproteinases), which play an important role in the containment of mycobacterial infection were studied in vivo and in vitro.

Results

A murine model of latent TB was developed, which was confirmed by CFU counts (<10⁴ in the lungs and spleen) and granuloma formation in lungs in the latent TB group. Also, the gene expression of hspX, tgs1, and tgs5 was upregulated, and after diabetes induction, blood glucose levels were >200 mg/dl. An in vitro study employing a THP-1 macrophage model of latent and active tuberculosis under normal and high glucose conditions showed that dormant bacilli were better contained in the presence of 5.5 mM glucose concentration as compared with active bacilli. However, the killing and restriction efficiency of macrophages decreased, and CFU counts increased significantly with an increase in glucose concentration.

Discussion

The decreased levels of MCP-1, decreased expression of mmp-9, and increased expression of mmp-1 in the latent group at high glucose concentrations could explain the failure of granuloma formation at high glucose conditions.

Impact of diabetes mellitus on immunity to latent tuberculosis infection

Tuberculosis (TB) is an infectious disease that poses a major health threat and is one of the leading causes of death worldwide. Following exposure to Mycobacterium tuberculosis (M.tb) bacilli, hosts who fail to clear M.tb end up in a state of latent tuberculosis infection (LTBI), in which the bacteria are contained but not eliminated. Type 2 diabetes mellitus (DM) is a noncommunicable disease that can weaken host immunity and lead to increased susceptibility to various infectious diseases. Despite numerous studies on the relationship between DM and active TB, data on the association between DM and LTBI remains limited. Immunological data suggest that LTBI in the presence of DM leads to an impaired production of protective cytokines and poly-functional T cell responses, accounting for a potential immunological mechanism that could leads to an increased risk of active TB. This review highlights the salient features of the immunological underpinnings influencing the interaction between TB and DM in humans.

Epidemiological Features and Impact of High Glucose Level on Virulence Gene Expression and Serum Resistance of Klebsiella pneumoniae Causing Liver Abscess in Diabetic Patients

Purpose

Klebsiella pneumoniae (K. pneumoniae) is a Gram-negative bacterium that is predominantly associated with liver abscesses in global diabetic patients. High levels of glucose in the surrounding of K. pneumonia increase its pathogenicity including capsular polysaccharide (CPS) and fimbriae. Other important virulent factors include outer membrane protein A (ompA) and regulator mucoid phenotype A (rmpA). The objective of this investigation was to elucidate the effects of high glucose on rmpA and ompA gene expression and serum resistance of K. pneumoniae causing liver abscess.

Patients and Methods

The clinical history of 57 patients suffering from K. pneumoniae-caused liver abscesses (KLA) was acquired and their clinical and laboratory manifestations in the presence or absence of diabetes were analyzed. The antimicrobial susceptibility, serotypes, and virulence genes were tested. Clinical isolates of 3 serotype-K1 hypervirulent K. pneumoniae (hvKP) were used to detect the effect of exogenous high glucose on rmpA, ompA, and clbB genes expression, and bacterial serum resistance.

Results

KLA patients with diabetes showed higher C-reactive protein (CRP) compared to non-diabetic KLA patients. Furthermore, the diabetic group showed increased incidences of sepsis and invasive infections, and their length of hospital stay was also prolonged. Pre-incubation of K. pneumoniae in high glucose (0.5%) concentration up-regulated rmpA, ompA, and clbB genes expression. However, cAMP supplementation, which was inhibited by environmental glucose, reversed the increase of rmpA and ompA in a cAMP-dependent manner. Moreover, hvKP strains incubated in high glucose also exhibited enhanced protection from serum killing.

Conclusion

High glucose levels reflected by poor glycemic control has increased gene expression of rmpA and ompA in hvKP by the cAMP signaling pathway and enhanced its resistance to serum killing, thus providing a new and reasonable explanation for the high incidences of sepsis and invasive infections in KLA patients with diabetes.

Bioinformatics analysis and consistency verification of a novel tuberculosis vaccine candidate HP13138PB

Background

With the increasing incidence of tuberculosis (TB) and the shortcomings of existing TB vaccines to prevent TB in adults, new TB vaccines need to be developed to address the complex TB epidemic.

Method

The dominant epitopes were screened from antigens to construct a novel epitope vaccine termed HP13138PB. The immune properties, structure, and function of HP13138PB were predicted and analyzed with bioinformatics and immunoinformatics. Then, the immune responses induced by the HP13138PB were confirmed by enzyme-linked immunospot assay (ELISPOT) and Th1/Th2/Th17 multi-cytokine detection kit.

Result

The HP13138PB vaccine consisted of 13 helper T lymphocytes (HTL) epitopes, 13 cytotoxic T lymphocytes (CTL) epitopes, and 8 B-cell epitopes. It was found that the antigenicity, immunogenicity, and solubility index of the HP13138PB vaccine were 0.87, 2.79, and 0.55, respectively. The secondary structure prediction indicated that the HP13138PB vaccine had 31% of α-helix, 11% of β-strand, and 56% of coil. The tertiary structure analysis suggested that the Z-score and the Favored region of the HP13138PB vaccine were -4.47 88.22%, respectively. Furthermore, the binding energies of the HP13138PB to toll-like receptor 2 (TLR2) was -1224.7 kcal/mol. The immunoinformatics and real-world experiments showed that the HP13138PB vaccine could induce an innate and adaptive immune response characterized by significantly higher levels of cytokines such as interferon-gamma (IFN-γ), tumor necrosis factor-α (TNF-α), interleukin-4 (IL-4), and IL-10.

Conclusion

The HP13138PB is a potential vaccine candidate to prevent TB, and this study preliminarily evaluated the ability of the HP13138PB to generate an immune response, providing a precursor target for developing TB vaccines.

Complicated Case of Multidrug-Resistant Tuberculosis with Multiple Comorbidities, Successfully Treated After Several Treatment Modifications

A 59-year-old man with relapsed pulmonary TB developed rifampin resistance. He presented with chronic untreated hepatitis B, which developed into liver cirrhosis, type 2 diabetes with diabetic retinopathy, and osteoarthritis of right knee. His initial MDR regimen included levofloxacin, cycloserine, bedaquiline, linezolid, and high-dose isoniazid. He developed episodes of linezolid-induced myelosuppression, resulting in temporary discontinuation and dose reduction, and ultimately, substitution of linezolid. On the seventh month of treatment, he developed severe depression with visual hallucination, resulting in cycloserine dose reduction. We maintained the principle of at least 4 active drugs throughout his treatment. He was considered cured after 26 months of treatment.

Demographic and Clinical Determinants of Tuberculosis and TB Recurrence: A Double-Edged Retrospective Study from Pakistan

Objective

TB recurrence is the second episode of TB after initial treatment bringing about an additional 7% load in TB burden intensified by 17.7% of multidrug-resistant recurrent cases. It is necessary to curb recurrence so that attempts to deal with active disease can be made more effective. This study aimed to characterize sociodemographic and clinical factors associated with recurrent TB in a high-burden setting. Methodology. A retrospective case-control study was carried out at two hospitals in Rawalpindi, Pakistan. TB patients and controls were included in the study. Sociodemographic and clinical data were collected by questionnaire from all subjects. Multivariate regression analysis was performed to determine factors associated with TB and TB recurrence respectively.

Results

In our study cohort, factors significantly associated with TB were low BMI (OR: 0.961 (CI 0.954-0.968), p < 0.001), female gender (OR: 2.065 (CI 1.922-2.219), p < 0.001), being single/unmarried (OR: 1.214 (CI 1.109-1.328), p=0.003), middle-income status (OR: 1.935 (CI 1.616-2.323), p < 0.001), smoking (OR: 1.567 (CI 1.435-1.710), p < 0.001), and diabetes mellitus (OR: 1.142 (CI 1.017-1.278), p=0.023). TB recurrence constituted 11.2% of patients presenting to the hospital. Compared with the first episode of TB, cases with recurrence were more likely to be older (OR: 1.011 (CI 1.004-1.017), p < 0.001), have disease awareness (OR: 1.906 (CI 1.486-2.437), p < 0.001), smear positive (OR: 2.384 (CI 1.650-3.536), p < 0.001), and be drug-resistant (OR: 5.615 (CI 4.265-7.386), p < 0.001).

Conclusion

In the present study cohort, low BMI, female gender, being single, middle-income status, being unemployed, smoking, and being diabetic came out to be the sociodemographic and clinical risk factors for TB. Further exploring the TB cases increasing age, drug resistance and smear positivity stood out to be the major sociodemographic and clinical factors of TB recurrence despite high disease awareness.

Risk factors for multidrug resistance in tuberculosis patients with diabetes mellitus

Objective

To study the risk factors and prediction models of multidrug resistance in patients with tuberculosis and diabetes and those with a history of tuberculosis treatment.

Methods

A total of 256 tuberculosis patients with diabetes who were registered in Luoyang city, Henan Province, from January 2018 to December 2021. Logistic regression analysis was performed to analyse the risk factors for multidrug resistance. ROC curves were used to analyse the predictive model for multidrug resistance.

Results

Age < 65 years old, HbA1c, and a history of tuberculosis treatment were independent risk factors for multidrug resistance in patients with tuberculosis and diabetes (P < 0.05). The area under the ROC curve of predictive model for MDR was 0.878 (95% CI (0.824, 0.932)). Age < 65 years old and HbA1c were independent risk factors for MDR in patients with TB and diabetes with a history of TB treatment. The area under the ROC curve of predictive model for MDR was 0.920 [95% CI (0.831, 0.999)].

Conclusion

The predictive model had certain prediction value for the risk of multidrug resistance in patients with tuberculosis and diabetes.

Characterization of chemokine and cytokine expression pattern in tuberculous lymphadenitis patient

INTRODUCTION

C-C chemokine receptor-2 (CCR-2) and C-C chemokine ligand-5 (CCL-5) play an important role in the migration of monocytes, macrophages, dendritic cells, and activated T cells against Mycobacterium tuberculosis (M.tb). Meanwhile, signal transducer and activator of transcription 3 (STAT-3) and suppressor of cytokine signaling 3 (SOCS-3), activated by interleukin (IL)-6 and IL-10 in tuberculosis (TB) infection, play an important role in phagocytosis, inflammation, and granulomatous-forming processes that may lead to TB treatment success or failure. However, there are no data about the expression of those markers in tuberculous lymphadenitis. The characterization of those markers is very critical to put a fundamental basis to understand the homing mechanism of tuberculous lymphadenitis.

AIM OF STUDY

The specific objective of this study is to characterize the expression pattern of CCR-2-CCL-5, IL-6, IL-10, STAT-3, and SOCS-3 in tuberculous lymphadenitis.

METHODS

The study was performed on 27 cases of tuberculous lymphadenitis node biopsies. The diagnosis of tuberculous lymphadenitis was based on the clinical criteria and the presence of the histological feature characteristic of TB granulomas. Afterward, immunohistochemistry was stained with CCR-2, CCL-5, IL-6, IL-10, STAT-3, and SOCS-3. A semiquantitative analysis of IHC images was performed to examine protein expression in stained preparations. The expression was also manually counted.

RESULTS

Compared with the normal area, both lymphocytes and macrophages expressed strongly CCR-2-, CCL-5, and IL-6, while IL-10, STAT-3-, and SOCS-3- were expressed lowly. There was a strong positive correlation between CCR-2 with IL-6 (p = 0,83) and IL-10 (p = 0,83).

CONCLUSION

The chronic infection process of tuberculous lymphadenitis was characterized by the expression of IL-10low, STAT-3low, SOCS-3low, CCR-2high, CCL-5high, and IL-6high.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, identifier NCT05202548.

Prediabetes and risk of active tuberculosis: a cohort study from Northern Taiwan

Background

Diabetes mellitus (DM) is a well-established risk factor for active tuberculosis (TB) infection. Despite the worldwide rapid increase in the prevalence of prediabetes, its impact on the risk of active TB remains largely unknown. This study aimed to investigate the relationship between prediabetes and risk of active TB in a large cohort study.

Methods

A total of 119 352 participants were screened from a community-based health screening programme in Northern Taiwan. Diabetes mellitus and prediabetes were defined by baseline fasting plasma glucose (FPG) and prescription of anti-diabetic drugs. Incident cases of active TB were identified from the National Tuberculosis Registry. Kaplan–Meier curves and Cox regression analysis were employed to estimate the hazard ratios for prediabetes and DM compared with normoglycaemia. Spline regression was performed to investigate the dose-response relationship between FPG level and risk of TB disease.

Results

At baseline, 27 404 (22.96%) participants had prediabetes and 10 943 (9.17%) participants had DM. After an average follow-up of 7.2 years, 322 TB cases occurred. The adjusted hazard ratio of developing active TB disease was 0.73 [95% confidence interval (CI) 0.55–0.97] for prediabetic and 1.48 (95% CI 1.11–1.98) for diabetic participants compared with normoglycaemic individuals. Spline regression revealed a U-shaped association between FPG level and risk of active TB disease, with the lowest risk at FPG around110 mg/dl. Sensitivity analyses were conducted to exclude factors such as potential confounders (including body mass index), misclassification of glycaemic level, and selection bias, and results showed that those factors could not explain the lower risk of active TB.

Conclusions

Prediabetes was associated with a 27% reduced risk of active TB disease compared with normoglycaemia. The biological mechanism of this inverse association and its implication for global nutrition transition and TB control should be further investigated.

Leukocyte metabolism in obese type 2 diabetic individuals associated with COVID-19 severity

Recent studies show that the metabolic characteristics of different leukocytes, such as, lymphocytes, neutrophils, and macrophages, undergo changes both in the face of infection with SARS-CoV-2 and in obesity and type 2 diabetes mellitus (DM2) condition. Thus, the objective of this review is to establish a correlation between the metabolic changes caused in leukocytes in DM2 and obesity that may favor a worse prognosis during SARS-Cov-2 infection. Chronic inflammation and hyperglycemia, specific and usual characteristics of obesity and DM2, contributes for the SARS-CoV-2 replication and metabolic disturbances in different leukocytes, favoring the proinflammatory response of these cells. Thus, obesity and DM2 are important risk factors for pro-inflammatory response and metabolic dysregulation that can favor the occurrence of the cytokine storm, implicated in the severity and high mortality risk of the COVID-19 in these patients.

Prevalence of Pulmonary Tuberculosis in Diabetic Patients: Epidemiology, Immunological Basis, and Its Amalgamated Management

Tuberculosis (TB) is one of the most widespread and infectious diseases in the world, which is brought on by Mycobacterium tuberculosis (MTB). Most infection lacks traditional signs. Latent TB is the name given to this ailment. Of these latent infections, 10% become active and cause illness. Fever, night sweats, a prolonged cough with blood-containing mucus, and weight loss are common signs of active TB infection. Diabetes, on the other hand, is a group of metabolic illnesses characterized by elevated serum glucose levels. It is a chronic metabolic condition brought on by a deficiency in insulin secretion or resistance. It is of two types, that is, type 1 and type 2. Among all the cases of diabetes, the occurrence of type 2 is more common and less fatal than type 1. The prevalence of diabetes is currently increasing in low- and middle-income nations. As both diabetes and TB come under the most widespread chronic condition; therefore, their combined effect is evaluated. In recent years, the higher occurrence of TB in patients with hyperglycemia has come to light. People with elevated blood glucose levels exhibit several risk factors that make them more vulnerable to contracting TB. This review provides information on epidemiological data about the prevalence of TB in patients with hyperglycemia. In addition, this paper discusses the immunological underpinnings of TB development in patients with diabetes mellitus and how glycemic management reduces the risk of TB infection. It illustrates how the clinical signs and radiographic evidence of TB differ between people with diabetes and healthy people and mentions diabetes and TB combined management.

Effect of Oral Antidiabetic Drugs on Tuberculosis Risk and Treatment Outcomes: Systematic Review and Meta-Analysis

Tuberculosis and diabetes mellitus are two global pandemics and rising public health problems. Recent studies suggest that oral antidiabetic drugs (OADs) could reduce the risk of tuberculosis and improve clinical outcomes. However, the evidence is controversial. Therefore, we aimed to assess the effect of OADs on the risk of tuberculosis and treatment outcomes. We systematically searched for six databases from inception to 31 August 2022. We followed a predefined PICO/PECO strategy and included two randomized controlled trials and sixteen observational studies. This study collects 1,109,660 participants, 908,211 diabetic patients, and at least 13,841 tuberculosis cases. Our results show that metformin decreases the risk of active tuberculosis by 40% (RR 0.60; 95% CI 0.47-0.77) in diabetic patients. In addition, metformin exhibits a dose-response gradient (medium doses reduce the risk of active tuberculosis by 45%, while high doses reduce this risk by 52%). On the other hand, DPP IV inhibitors increase the risk of active tuberculosis by 43% (RR 1.43; 95% CI 1.02-2.02). Subgroup analysis showed that study design and metformin dose accounted for the heterogeneity. We conclude that metformin significantly protects against active tuberculosis among diabetic patients. On the contrary, DPP IV inhibitors could increase the risk of developing active tuberculosis.

Prevalence of proximate risk factors of active tuberculosis in latent tuberculosis infection: A cross-sectional study from South India

The prevalence of proximate risk factors for active tuberculosis (TB) in areas of high prevalence of latent tuberculosis infection (LTBI) is not clearly understood. We aimed at assessing the prevalence of non-communicable multi-morbidity focusing on diabetes mellitus (DM), malnutrition, and hypertension (HTN) as common risk factors of LTBI progressing to active TB. In a cross-sectional study, 2,351 adults (45% male and 55% female) from villages in the Kancheepuram district of South India were enrolled between 2013 and 2020. DM was defined as HbA1c >6.4%, undernutrition was defined as low body mass index (LBMI) <18.5 kg/m², obesity was classified as BMI ≥25 kg/m², HTN was reported as systolic pressure >130 mmHg, and LTBI was defined as positive (≥ 0.35 international units/ml) by QuantiFERON Gold In-Tube assay. A total of 1,226 individuals (52%) were positive for LTBI out of 2351 tested individuals. The prevalence of DM and pre-diabetes mellitus (PDM) was 21 and 35%, respectively, HTN was 15% in latent tuberculosis (LTB)-infected individuals. The association of DM [odds ratio (OR)]; adjusted odds ratio (aOR) (OR = 1.26, 95% CI: 1.13-1.65; aOR = 1.19, 95% CI: 1.10-1.58), PDM (OR = 1.11, 95% CI: 1.0-1.35), and HTN (OR = 1.28, 95% CI: 1.11-1.62; aOR = 1.18, 95% CI: 1.0-1.56) poses as risk factors of LTBI progression to active TB. The prevalence of LBMI 9% (OR = 1.07, 95% CI: 0.78-1.48) and obesity 42% (OR = 0.85, 95% CI: 0.70-1.03) did not show any statistically significant association with LTB-infected individuals. The present evidence of a high burden of multi-morbidity suggests that proximate risk factors of active TB in LTBI can be managed by nutrition and lifestyle modification.

Chronic hyperglycemia drives alterations in macrophage effector function in pulmonary tuberculosis

Diabetes mellitus (DM) alters immune responses and given the rising prevalence of DM in tuberculosis (TB) endemic countries; hyperglycemia can be a potential risk factor for active TB development. However, the impact of hyperglycemia on TB-specific innate immune response in terms of macrophage functions remains poorly addressed. We assessed macrophage effector functions in uncontrolled DM patients with or without TB infection (PTB+DM and DM), non-diabetic TB patients (PTB), and non-diabetic-uninfected controls. Phagocytic capacity against BCG and surface expression of different pattern recognition receptors (PRRs) (CD11b, CD14, CD206, MARCO, and TLR-2) were measured via flow cytometry. Effector molecules (ROS and NO) required for bacterial killing were assessed via DCFDA and Griess reaction respectively. A systematic dysregulation in phagocytic capacity with concurrent alterations in the expression pattern of key PRRs (CD11b, MARCO, and CD206) was observed in PTB+DM. These altered PRR expressions were associated with decreased phagocytic capacity of macrophages. Similarly, ROS was aberrantly higher while NO was lower in PTB+DM. These altered macrophage functions were positively correlated with increasing disease severity. Our results highlight several key patterns of immune dysregulation against TB infection under hyperglycemic conditions and highlight a negative impact of hyperglycemia with etiology and progression of TB.

Pulmonary tuberculosis and diabetes mellitus: Clinical profile and outcomes

Background

India is endemic for Tuberculosis (TB), contributing to the world's highest number of active cases. Diabetes (DM), with its increasing burden in India, could contribute to adverse outcomes among patients with TB.

Methods

Consecutive patients with sputum smear positive pulmonary tuberculosis were included in the study. We defined cases as those patients with diabetes at recruitment. Controls were non diabetics (NDM). Sputum samples for AFB smears, AFB culture and Xpert PCR along with blood samples for glycosylated Haemoglobin and glucose levels were collected at recruitment and at 6 months from patients with sputum positive pulmonary TB. Blood glucose levels and sputum smears were repeated at 2 months and monthly till they tested negative. The primary outcome studied was mortality at 6 month follow-up. The secondary outcomes included the time to conversion of sputum smears and cure rates between cases and controls.

Results

We recruited 124 patients of which 68 were cases. Mortality after therapy was 15% in cases and 7% in controls, however, the difference was not statistically significant. Equal proportions in each group (Diabetics: 9% vs. NDM 9%) had persistent smear positivity at 2 months. There was no association between delayed sputum conversion and uncontrolled diabetes. Only about 57% of cases and 50% of controls were documented to have completed treatment or been cured. A significant reduction in HbA1c after 6 months of Antituberculous therapy was noted among the cases. [Mean difference - 1.76, P-value - 0.001, 95% CI of difference - (1.01 - 2.52)].

Conclusions

Diabetes did not have adverse outcomes in the form of increased mortality or delayed sputum conversion rates. The high proportion of loss to follow-up seems to be a trend of concern, which should be addressed emergently.

Tuberculosis treatment outcomes of diabetic and non-diabetic TB/HIV co-infected patients: A nationwide observational study in Brazil

Background

Tuberculosis (TB) is a worldwide public health problem, especially in countries that also report high numbers of people living with HIV (PLWH) and/or diabetes mellitus (DM). However, the unique features of persons with TB-HIV-DM are incompletely understood. This study compared anti-TB treatment (ATT) outcomes of diabetic and non-diabetic TB/HIV co-infected patients.

Methods

A nationwide retrospective observational investigation was performed with data from the Brazilian Tuberculosis Database System among patients reported to have TB-HIV co-infection between 2014 and 2019. This database includes all reported TB cases in Brazil. Exploratory and association analyses compared TB treatment outcomes in DM and non-DM patients. Unfavorable outcomes were defined as death, treatment failure, loss to follow-up or recurrence. Multivariable stepwise logistic regressions were used to identify the variables associated with unfavorable ATT outcomes in the TB-HIV population.

Results

Of the 31,070 TB-HIV patients analyzed, 999 (3.2%) reported having DM. However, in these TB-HIV patients, DM was not associated with any unfavorable treatment outcome [adjusted Odds Ratio (aOR): 0.97, 95% CI: 0.83-1.12, p = 0.781]. Furthermore, DM was also not associated with any specific type of unfavorable outcome in this study. In both the TB-HIV group and the TB-HIV-DM subpopulation, use of alcohol, illicit drugs and tobacco, as well as non-white ethnicity and prior TB were all characteristics more frequently observed in persons who experienced an unfavorable ATT outcome.

Conclusion

DM is not associated with unfavorable TB treatment outcomes in persons with TB-HIV, including death, treatment failure, recurrence and loss to follow up. However, consumption habits, non-white ethnicity and prior TB are all more frequently detected in those with unfavorable outcomes in both TB-HIV and TB-HIV-DM patients.

Screening of latent tuberculosis infection among patients with diabetes mellitus from a high-burden area in Brazil

Although several cohort studies have raised the important association between diabetes mellitus (DM) and latent tuberculosis infection (LTBI), evidences are limited and controversial. Furthermore, it is well documented that the poor glycemic control may exacerbate the risk for active TB. Thus, the monitoring of diabetic patients living in high-incidence areas for TB is an important concern in views of available diagnostic tests for LTBI. In this cross-sectional study, we estimate the association of DM and LTBI among diabetic patients classified as type-1 DM (T1D) or type-2 DM (T2D) living in Rio de Janeiro, RJ, Brazil - considered a high TB burden region of these country. Non-DM volunteers were included as endemic area healthy controls. All participants were screened for DM using glycosylated-hemoglobin (HbA_1c) and for LTBI using the QuantiFERON-TB Gold in Tube (QFT-GIT). Demographic, socioeconomic, clinical and laboratorial data were also assessed. Among 553 included participants, 88 (15.9%) had QFT-GIT positive test, of which 18 (20.5%) were non-DM, 30 (34.1%) T1D and 40 (45.4%) T2D. After adjustments for potential baseline confounders, age, self-reported non-white skin color and an active TB case in the family were significantly associated with LTBI among the studied population by using a hierarchical multivariate logistic regression analysis. Additionally, we verified that T2D patients were able to produce significant increased interferon-gamma (IFN-γ) plasma levels in response to Mycobacterium tuberculosis-specific antigens, when compared to non-DM individuals. Altogether, our data showed an increased prevalence of LTBI among DM patients, albeit non-statistically significant, and point out to important independent factors associated with LTBI, which deserve attention in monitoring patients with DM. Moreover, QFT-GIT test seems to be a good tool to screening LTBI in this population, even in a high TB burden area.

The Impact of Diabetes and Prediabetes on Prevalence of Mycobacterium tuberculosis Infection Among Household Contacts of Active Tuberculosis Cases in Ethiopia

Background

It is uncertain whether diabetes affects the risk of developing latent tuberculosis infection (LTBI) following exposure to Mycobacterium tuberculosis (Mtb). We assessed the relationship of diabetes or prediabetes and LTBI among close and household contacts (HHCs) of patients with active pulmonary tuberculosis (TB) disease in Addis Ababa, Ethiopia.

Methods

In this cross-sectional study, we performed interferon-γ release assays, TB symptom screening, and point-of-care glycolated hemoglobin (HbA1c) testing among HHCs of active TB cases. Diabetes status was classified into diabetes (HbA1c ≥6.5% or self-reported diagnosis), prediabetes (5.7%-6.4%), and euglycemia (≤5.6%). Multivariable logistic regression was used to determine the association of diabetes with LTBI.

Results

Among 597 study participants, 123 (21%) had dysglycemia including diabetes (n = 31) or prediabetes (n = 92); 423 (71%) participants were diagnosed with LTBI. Twelve of 31 (39%) HHCs with diabetes were previously undiagnosed with diabetes. The prevalence of LTBI among HHCs with diabetes, prediabetes, and euglycemia was 87% (27/31), 73% (67/92), and 69% (329/474), respectively. In multivariable analysis adjusted for age, sex, and HIV status, the odds of LTBI among HHCs with diabetes were 2.33 (95% confidence interval [CI], .76-7.08) times the odds of LTBI without diabetes. When assessing interaction with age, the association of diabetes and LTBI was robust among participants aged ≥40 years (adjusted odds ratio [aOR], 3.68 [95% CI, .77-17.6]) but not those <40 years (aOR, 1.15 [95% CI, .22-6.1]).

Conclusions

HHCs with diabetes may be more likely to have LTBI than those with euglycemia. Further investigations are needed to assess mechanisms by which diabetes may increase risk of LTBI after Mtb exposure.

In silico Analysis of Peptide-Based Biomarkers for the Diagnosis and Prevention of Latent Tuberculosis Infection

Background

Latent tuberculosis infection (LTBI) is the primary source of active tuberculosis (ATB), but there are no specific methods for diagnosing and preventing LTBI.

Methods

Dominant T and B cell epitopes predicted from five antigens related to LTBI and Mycobacterium tuberculosis region of difference (LTBI-RD) were used to construct a novel polypeptide molecule (PPM). Then, the physicochemical properties, secondary structure, tertiary structure of the PPM, and its binding ability to toll-like receptor 2 (TLR2) and TLR4 were analyzed by bioinformatics tools. Finally, immune stimulation and expression optimization of the PPM were carried out.

Results

Four helper T lymphocytes (HTL) epitopes, five cytotoxic T lymphocytes (CTL) epitopes, and three B cell epitopes were predicted and screened from five LTBI-RD related antigens. These epitopes were connected in series with linkers and adjuvants to construct a novel PPM termed C543P. The results indicated that antigenicity and immunogenicity scores of the C543P candidate were 0.936399 and 1.36469, respectively. The structural analysis results showed that the C543P candidate had good stability. Its secondary structure contained 43.6% α-helix, the Z-score after tertiary structure optimization was −7.9, and the Ramachandran diagram showed that 88.77% amino acid residues of the C543P candidate were in the allowable region. Furthermore, the C543P candidate showed an excellent affinity to TLR2 (−1091.7kcal/mol) and TLR4 (−1102.7kcal/mol). In addition, we also analyzed the immunological characteristics of the C543P candidate. Immune stimulation prediction showed that the C543P candidate could effectively activate T and B lymphocytes and produce high levels of Th1 cytokines such as IFN-γ and IL-2.

Conclusion

We constructed a novel PPM with acceptable antigenicity, immunogenicity, stability, and ability to induce robust immune responses. This study provides a new diagnostic biomarker or peptides-based vaccine for LTBI diagnosis and prevention.

Cellular Immunity of Patients with Tuberculosis Combined with Diabetes

Tuberculosis (TB) is one of humanity's three major infectious diseases. Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia due to impaired insulin secretion or impaired insulin function. It has been reported that DM is a primary risk factor for TB disease. Given the increasing public health threat to people's health, more and more studies have focused on diabetes complicated by TB. Hyperglycemia can affect the function of human immune cells, promote primary infections and reactivation of TB, and increase the susceptibility and severity of TB. However, the immunological mechanism behind it is still not clear. By reviewing the related articles on tuberculosis complicated with diabetes published in recent years, this paper expounds on the effect of hyperglycemia on innate immunity and adaptive immunity of patients with TB. This review provides new insights for elucidating the immunological mechanism of TB complicated with DM and lays the foundation for finding potential targets for preventing and treating TB combined with DM.

Extensive Radiological Manifestation in Patients with Diabetes and Pulmonary Tuberculosis: A Cross-Sectional Study

Background

Diabetes mellitus (DM) is believed to affect tuberculosis (TB) at multiple levels in disease control and treatment efficacy, but clinical and radiological presentation resulting from interaction of the two diseases is not known.

Methods

A cross-sectional study was conducted on data obtained from medical records of 438 patients confirmed with TB-DM comorbidity at the Third people's hospital of Shenzhen from May 01, 2014, to April 30, 2019. Their CT images were reviewed, and patients were divided into subgroups according to lung cavitation: with and without cavities, and number of segments showing pulmonary infiltration: <4 segment, 4-8 segment, >8 segment infiltrates. We then compared clinical parameters between these groups.

Results

The median age of the patients was 50.0 years (IQR 43.3-56.0) and 86% (n=375) of them were male. Pulmonary cavities were found in 80.8% patients. About 42.7% and 27.2% patients were seen to have infiltration involving 4-8 and >8 lung segments, respectively. Patients presented with cavitation and infiltration involving a greater number of lung segments had significantly higher values of WBC, MONO%, GRA%, CRP, lower LYN% level and higher bacterial burden in sputum (P<0.001). Higher HbA1c and FBG were only observed in patients with lung cavities (P<0.001). There was no difference in positive ELISPOT.TB and PCT level between the groups regardless of presence or absence of lung cavity (P>0.9 and P=0.1 respectively). Lower HGB, ALB and higher PCT were observed in patients with infiltration involving more lung segments.

Conclusion

Hyper-inflammation in peripheral blood was significantly associated with cavity and the number of lung lesions. Hyperglycemia was significantly associated with the development of lung cavity. Glycemic control and inflammation influenced radiographic manifestations in patients with TB-DM.

Tuberculosis Predictive Index for Type 2 Diabetes Mellitus Patients Based on Biological, Social, Housing Environment, and Psychological Well-Being Factors

Indonesia is currently undergoing an epidemiological transition, with the double burden of disease due to increasing industrialization and urbanization leading to an increase in the prevalence of non-communicable diseases such as obesity and diabetes. On the other hand, the prevalence of infectious diseases such as tuberculosis remains high. Several factors were considered as risk factors in tuberculosis coincidence with type 2 diabetes mellitus. The purpose of this study was to develop a predictive index for tuberculosis in type 2 diabetes mellitus patients based on their biological, social, and environmental factors, and their psychological well-being as well. This case-control study involved 492 respondents consisting of 246 type 2 diabetes mellitus patients The variables studied were biological and social factors, the quality of their housing, and psychological well-being. Data analysis was conducted using a logistic regression test. The results showed that the predictive index formula was as follows: −3.218 + 0.867 × age + 1.339 × sex + 1.493 × history of contact with previous patient + 1.089 × glycemic control + 1.622 × tuberculosis clinical symptoms + 1.183 × body mass index + 0.891 × duration of diabetes mellitus + 0.454 × area of ventilation + 0.583 × psychological well-being. It is suggested that health workers, especially in primary health care facilities, will be able to increase the awareness of the risk of the coincidence of diabetes mellitus with tuberculosis.

Interplay Between the Immune and Endocrine Systems in the Lung: Implications for TB Susceptibility

The role of the endocrine system on the immune response, especially in the lung, remains poorly understood. Hormones play a crucial role in the development, homeostasis, metabolism, and response to the environment of cells and tissues. Major infectious and metabolic diseases, such as tuberculosis and diabetes, continue to converge, necessitating the development of a clearer understanding of the immune and endocrine interactions that occur in the lung. Research in bacterial respiratory infections is at a critical point, where the limitations in identifying and developing antibiotics is becoming more profound. Hormone receptors on alveolar and immune cells may provide a plethora of targets for host-directed therapy. This review discusses the interactions between the immune and endocrine systems in the lung. We describe hormone receptors currently identified in the lungs, focusing on the effect hormones have on the pulmonary immune response. Altered endocrine responses in the lung affect the balance between pro- and anti-inflammatory immune responses and play a role in the response to infection in the lung. While some hormones, such as leptin, resistin and lipocalin-2 promote pro-inflammatory responses and immune cell infiltration, others including adiponectin and ghrelin reduce inflammation and promote anti-inflammatory cell responses. Furthermore, type 2 diabetes as a major endocrine disease presents with altered immune responses leading to susceptibility to lung infections, such as tuberculosis. A better understanding of these interactions will expand our knowledge of the mechanisms at play in susceptibility to infectious diseases and may reveal opportunities for the development of host-directed therapies.

Tim-3 Expression Causes NK Cell Dysfunction in Type 2 Diabetes Patients

Type 2 diabetes mellitus (T2DM) is characterized by high blood glucose levels and chronic low-grade inflammation. It shows a strong association with obesity and immune dysfunction, which makes T2DM patients more susceptible to infectious diseases. NK cells play an important role in pathogen control and tumor surveillance. However, whether NK cell distribution and functional status are altered in T2DM is unclear. To address this issue, we compared surface receptor expression and cytokine production between peripheral blood NK cells from 90 T2DM patients and 62 age- and sex-matched healthy controls. We found a significantly lower frequency and absolute number of NK cells in patients than in controls. Interestingly, the expression of inhibitory receptor Tim-3 was significantly increased, while the expression of the activating receptor NKG2D was significantly decreased, in T2DM NK cells. Both TNF-α secretion and degranulation capacity (evidenced by CD107a expression) were dampened in NK cells from patients. The expression of Tim-3 on NK cells correlated positively with both HbA1c and fasting blood glucose levels and negatively with the percentage and absolute number of total NK cells and was associated with increased NK cell apoptosis. In addition, Tim-3 expression on NK cells negatively correlated with TNF-α production, which could be restored by blocking Galectin-9/Tim-3 pathway. Our results suggest that NK cell dysfunction secondary to augmented Tim-3 expression occurs in T2DM patients, which may partly explain their increased susceptibility to cancer and infectious disease.

The Association Between Diabetes Mellitus and the Risk of Latent Tuberculosis Infection: A Systematic Review and Meta-Analysis

Background

The estimated global latent tuberculosis infection (LTBI) burden indicates a large reservoir of population at risk of developing active tuberculosis (TB). Previous studies suggested diabetes mellitus (DM) might associate with LTBI, though still controversial. We aimed to systematically assess the association between DM and LTBI.

Methods

We searched PubMed, Embase, Cochrane Library and Web of Science. Observational studies reporting the number of LTBI and non-LTBI individuals with and without DM were included. Random-effects or fixed-effects models were used to estimate the pooled effect by risk ratios (RRs) and odds ratios (ORs) and its 95% confidence interval (CI), using the original number of participants involved.

Results

20 studies involving 4,055,082 participants were included. The pooled effect showed a significant association between DM and LTBI (for cohort studies, RR = 1.62, 95% CI: 1.02-2.56; for cross-sectional studies, OR = 1.55, 95% CI: 1.30-1.84). The pooled OR was high in studies with healthcare workers (5.27, 95% CI: 1.52-8.20), refugees (2.88, 95% CI: 1.93-4.29), sample size of 1,000-5,000 (1.99, 95% CI: 1.49-2.66), and male participants accounted for less than 40% (2.28, 95% CI: 1.28-4.06). Prediabetes also associated with LTBI (OR = 1.36, 95% CI: 1.01-1.84).

Conclusion

The risk of LTBI was found to be a 60% increase in DM patients, compared with non-DM patients. LTBI screening among DM patients could be of vital importance. More studies are needed to explore appropriate strategies for targeted LTBI screening among DM patients.

Impact of Diabetes Mellitus on the Immunity of Tuberculosis Patients: A Retrospective, Cross-Sectional Study

Background

Tuberculosis (TB) is an infectious disease that poses a significant health threat and is one of the leading causes of death worldwide. Diabetes mellitus (DM) has high morbidity and mortality rates. Previous studies have reported that comorbidities can influence one another and aggravate immune disorders. A systematic and comprehensive evaluation of the immune status of patients with TB and DM (TB-DM) is helpful for early clinical immune intervention and for promoting the recovery of patients with TB-DM.

Methods

This study included 159 patients with TB without DM (TB-NDM) and 168 patients with TB-DM. Interferon-γ (IFN-γ) release assays (IGRAs) and TB-specific antibodies against 38kD+16kD proteins were used to detect humoral and cellular immune responses. Flow cytometry was used to analyze the absolute counts of the lymphocyte subsets.

Results

There was no significant difference in the positive rate of enzyme-linked immunospot (ELISPOT) assays, enzyme linked immunosorbent assay (ELISA), and 38kD+16kD antibodies between the TB-DM and TB-NDM groups. Pulmonary lobe lesion and cavity formation rates were significantly higher in patients with TB-DM with poor glycemic control than patients with TB-NDM and TB-DM with normal glycemic control. The absolute counts of T lymphocytes, CD8+ T lymphocytes, and B lymphocytes in patients with TB-DM were markedly lower than those in patients with TB-NDM. The absolute counts of T lymphocytes and CD8+ T lymphocytes in patients with TB-DM and hyperglycemia were lower than those in patients with euglycemia. Linear regression analysis revealed that the absolute counts of total T lymphocytes, CD8+ T lymphocytes, and NK cells in patients with TB-DM significantly decreased with increasing fasting blood glucose (FBG) levels.

Conclusion

Hyperglycemia is a risk factor for pulmonary cavity formation and lobe lesions in patients with TB-DM and suppresses the absolute counts of total T lymphocytes, CD8+ T lymphocytes, and NK cells in patients with TB-DM. The potential mechanism may involve the downregulation of innate and adaptive immune responses.